Overcoming the Drawbacks of Sulpiride by Means of New Crystal Forms

Development of Glycerosomal pH Triggered In Situ Gelling System to Ameliorate the Nasal Delivery of Sulpiride for Pediatric Psychosis

Sulpiride (Sul) is a medication that blocks dopamine D2 receptors. It is used to treat gastrointestinal disturbances and has antipsychotic effects depending on the dose given. Sulpiride is subject to P-glycoprotein efflux, resulting in limited bioavailability and erratic absorption. Hence, the aim of this study was to generate a glycerosomal in situ gel of sulpiride for intranasal administration, specifically targeting children with schizophrenia who may have difficulty swallowing traditional solid medications, for enhancing its bioavailability. This study aimed to demonstrate the efficacy of intranasal administration of glycerin-encapsulated lipid-nanovesicles (glycerosomes) mixed with in situ gels for prolonged release of anti-psychotic medication. A Box-Behnken design was utilized to create sulpiride-loaded glycerosomes (Sul-GMs), with the lipid amount (A), glycerin concentration (B), and sonication time (C) acting as independent variables. Their impact on the entrapment efficiency, EE% (Y1), and in vitro drug release (Y2) were evaluated. The sulpiride EE% showed an increase when the glycerin concentration was raised to 25% v/v. Nevertheless, when the glycerin concentration was raised to 40% v/v, there was a notable decrease in the EE%. The optimized glycerosome was added to pH triggered carbopol 974P in situ gel formulations including HPMC K15M with different concentrations. The in situ gel formulation (G3) comprising 0.6% carbopol 974P and 0.6% hydroxypropyl methyl cellulose-K15M (HPMC K15M) demonstrated suitable pH, viscosity, desired gel strength, spreadability, and mucoadhesive strength. Consequently, it was selected for in vitro study, ex vivo permeation investigation, and in vivo evaluations. The glycerosomal in situ gel exhibited favorable ex vivo permeability of SU when applied to the nasal mucosa. The pharmacokinetic investigation revealed that the optimized Sul-loaded glycerosomal in situ gel exhibited a significant fourfold and twofold enhancement in systemic bioavailability compared to both the control gel and the commercially available formulation. Finally, the intranasal administration of Sul-loaded glycerosomal in situ gel is a promising alternative to oral treatment for pediatric patients with psychosis.

Shifting the Focus from Dissolution to Permeation: Introducing the Meso-fluidic Chip for Permeability Assessment (MCPA)

In response to the growing ethical and environmental concerns associated with animal testing, numerous in vitro tools of varying complexity and biorelevance have been developed and adopted in pharmaceutical research and development. In this work, we present one of these tools, i.e., the Meso-fluidic Chip for Permeability Assessment (MCPA), for the first time. The MCPA combines an artificial barrier (PermeaPad®) with an organ-on-chip device (MIVO®) and real-time automated concentration measurements, to yield a sustainable, yet effortless method for permeation testing. The system offers three major physiological aspects, i.e., a biomimetic membrane, an optimal membrane interfacial area-to-donor-volume-ratio (A/V) and a physiological flow on the acceptor/basolateral side, which makes the MPCA an ideal candidate for mechanistic studies and excellent in vivo bioavailability predictions. We validated the method with a handful of assorted drug compounds in unstirred and stirred donor conditions, before exploring its applicability as a tool for dissolution/permeation testing on a BCS class III/I drug (pyrazinamide) crystalline adducts and BCS class II/IV (hydrocortisone) amorphous solid dispersions. The results were highly reproducible and clearly displayed the method's potential for evaluating the performance of enabling formulations, and possibly even predicting in vivo performance. We believe that, upon further development, the MCPA will serve as a useful in vitro tool that could push sustainability into pharmaceutics by refining, reducing and replacing animal testing in early-stage drug development.